@article{MAN_1933__107_159597,
     author = {G. Gentzen},
     title = {\"Uber die {Existenz} unabh\"angiger {Axiomensysteme} zu unendlichen {Satzsystemen}},
     journal = {Mathematische Annalen},
     pages = {329--350},
     publisher = {mathdoc},
     volume = {107},
     year = {1933},
     zbl = {0005.33803},
     url = {http://geodesic.mathdoc.fr/item/MAN_1933__107_159597/}
}